This application relates to a passive activation of a home security system. Vehicles and homes are becoming more electrically complex. Vehicles are now provided with a number of electronic security systems such as door locks, trunk locks, etc. These security systems are typically actuated by a remote signaling device known as a key fob signaling device. Key fob signaling devices are also becoming incorporated into the vehicle keys themselves. Such combinations are provided with the ability to transmit code to other security devices when in the vehicle. As one major example of this function is the use of an immobilizer system which communicates with the key to determine whether a proper key is in the ignition.
The vehicle keys and/or key fobs are typically provided with an RF link for transmitting code and unlocking vehicle security systems remotely. Further, they are often provided with an LF link for actuating or allowing actuation of a vehicle ignition.
Vehicles are often also provided with a garage door opener. Garage door openers are actuated from the interior of the vehicle and send a code to the garage door for opening the garage door as the vehicle approaches. Such actuation are also known for other home security systems such as home door locks, fences, etc.
It has been proposed to have passive entry systems for home security functions, such as garage doors. One example utilizes a magnetic sensor on a vehicle, which sends a signal from a vehicle when magnetic members in the driveway are passed over by the vehicle. These systems act to passively actuate a signal to open the home security system (garage door). These systems are somewhat deficient in that they require modification to the home itself, and further could actuate the transmission of a signal by any vehicle passing over the magnetic members which is provided with the particular security system. Thus, it would be desirable to develop a system which only actuates the transmission of a signal if the appropriate vehicle is approaching the home security system.
In the disclosed embodiment of this invention a sensor senses the presence of a vehicle approaching a home security system. The sensor then generates a challenge signal from the home security system which is directed at the vehicle. The challenge generates a response from the vehicle signaling device, and that response is compared to an expected response. If the response corresponds to the expected response, then the home security system is actuated.
The technology for providing the coded information associated with each vehicle is known and forms no portion of this invention. A worker in this art would be well aware of a number of encoding options and algorithms for encoding signals such as garage door opener signals.
In a preferred embodiment of this invention, the signaling device for sending the passive signal will be incorporated into the key or key fob in the vehicle. Co-pending patent application Ser. No. 09/661,351 filed on Sep. 14, 2000 and entitled xe2x80x9cGarage Door Opener Signal Incorporated Into Vehicle Key/Fob Combinationxe2x80x9d and invented by the inventor of this application discloses several benefits for incorporating the home security actuation function into the key or key fob. One additional function that is directed to this application is that the key/key fob would be a so called xe2x80x9ccombi-keyxe2x80x9d. Such systems include an RF transmitter, and also an LF receiver and transmitter for use with the immobilizer system. In such a case, no modification to the key/key fob is necessary. Instead, the challenge and corresponding response could be sent as an LF signal as the vehicle approaches the home security system. This is also beneficial in that the signal will not travel an undue distance, which might jeopardize the security of the signal.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.